Some embodiments described herein relate generally to systems and methods for minimizing power consumption in integrated circuits (ICs) in embedded systems.
Embedded systems can be used in a variety of applications including, for example, providing monitoring, sensing, control, or security functions. Such embedded systems are generally tailored to specific applications, according to relatively severe constraints on size, power consumption, or environmental survivability.
In particular, one class of embedded system can include sensor nodes, such as sensor nodes for sensing or monitoring one or more physiologic parameters. Sensor nodes are implemented as ICs and can provide significant benefit to health care providers, such as enabling continuous monitoring, actuation, and logging of physiologic information, facilitating automated or remote follow-up, or providing one or more alerts in the presence of deteriorating physiologic status. The physiologic information obtained using such a sensor node can be transferred to other systems that can be used to help diagnose, prevent, and respond to various illnesses such as diabetes, asthma, cardiac conditions, or other illnesses or conditions.
A sensor node can provide particular value to a subject or care giver if the sensor node includes certain features such as, for example, long-term monitoring capability and/or wearability. A long lifetime for a sensor node without maintenance, replacement, or manual recharging becomes ever more important as health care costs escalate or as more care providers attempt to transition to remote patient follow-up and telemedicine. It is believed that generally-available sensor nodes are precluded from widespread adoption because of a lack of extended operational capability or wearability.
Minimizing or reducing power consumption by employing power management techniques is desirable in integrated circuit (IC) design. Known techniques for minimizing or reducing power consumption such as, for example, dynamic voltage scaling (DVS), where the power supply of an IC is modulated according to its performance needs, has several drawbacks in practical implementation such as the output capacitor (CL) of the DC-DC converter is typically large that leads to large settling time. Additionally, the energy stored in a capacitor is typically also high and thus changing the output voltage involves energy overheads. Typically such overheads limits the rate at which the VDD can be scaled and hence the amount of energy that can be saved.
Other known methods such as, for example, panoptic dynamic voltage scaling (PDVS) include drawbacks such as the use of at least three DC-DC converters, different routing devices, switches and level-converters that are used to implement the PDVS technology. Such a large number of components involve the use of high circuit area and high costs for implementation.
Accordingly, a need exists for apparatus and methods for implementing energy efficient and cost efficient methods to minimize power consumption by ICs used in embedded systems.